From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FC6AC6369F for ; Sat, 19 Jan 2019 19:51:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D15C22087E for ; Sat, 19 Jan 2019 19:51:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729490AbfASTvT convert rfc822-to-8bit (ORCPT ); Sat, 19 Jan 2019 14:51:19 -0500 Received: from coyote.holtmann.net ([212.227.132.17]:48093 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729334AbfASTvO (ORCPT ); Sat, 19 Jan 2019 14:51:14 -0500 Received: from marcel-macpro.fritz.box (p4FF9FD60.dip0.t-ipconnect.de [79.249.253.96]) by mail.holtmann.org (Postfix) with ESMTPSA id 2C453CF353; Sat, 19 Jan 2019 20:58:58 +0100 (CET) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 12.2 \(3445.102.3\)) Subject: Re: [PATCH v4 5/5] Bluetooth: btusb: Use the hw_reset method to allow resetting the BT chip From: Marcel Holtmann In-Reply-To: <20190118223407.64818-5-rajatja@google.com> Date: Sat, 19 Jan 2019 20:51:11 +0100 Cc: Johan Hedberg , Greg Kroah-Hartman , "David S. Miller" , Dmitry Torokhov , Alex Hung , linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, netdev@vger.kernel.org, rajatxjain@gmail.com, dtor@google.com, raghuram.hegde@intel.com, chethan.tumkur.narayan@intel.com, sukumar.ghorai@intel.com Content-Transfer-Encoding: 8BIT Message-Id: <710EDC24-B0F2-4FDB-9C30-F78CDF74C0E5@holtmann.org> References: <20181117010748.24347-1-rajatja@google.com> <20190118223407.64818-1-rajatja@google.com> <20190118223407.64818-5-rajatja@google.com> To: Rajat Jain X-Mailer: Apple Mail (2.3445.102.3) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org Hi Rajat, > If the platform provides it, use the reset gpio to reset the BT > chip (requested by the HCI core if needed). This has been found helpful > on some of Intel bluetooth controllers where the firmware gets stuck and > the only way out is a hard reset pin provided by the platform. > > Signed-off-by: Rajat Jain > --- > v4: Use data->flags instead of clearing the quirk in btusb_hw_reset() > v3: Better error handling for gpiod_get_optional() > v2: Handle the EPROBE_DEFER case. > > drivers/bluetooth/btusb.c | 45 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 45 insertions(+) > > diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c > index 59869643cc29..7cf1e4f749e9 100644 > --- a/drivers/bluetooth/btusb.c > +++ b/drivers/bluetooth/btusb.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > #include > > #include > @@ -439,6 +440,7 @@ static const struct dmi_system_id btusb_needs_reset_resume_table[] = { > #define BTUSB_BOOTING 9 > #define BTUSB_DIAG_RUNNING 10 > #define BTUSB_OOB_WAKE_ENABLED 11 > +#define BTUSB_HW_RESET_DONE 12 I think you mean BTUSB_HW_RESET_ACTIVE or BTUSB_HW_RESET_IN_PROGRESS. > > struct btusb_data { > struct hci_dev *hdev; > @@ -476,6 +478,8 @@ struct btusb_data { > struct usb_endpoint_descriptor *diag_tx_ep; > struct usb_endpoint_descriptor *diag_rx_ep; > > + struct gpio_desc *reset_gpio; > + > __u8 cmdreq_type; > __u8 cmdreq; > > @@ -491,6 +495,30 @@ struct btusb_data { > int oob_wake_irq; /* irq for out-of-band wake-on-bt */ > }; > > + > +static void btusb_hw_reset(struct hci_dev *hdev) > +{ > + struct btusb_data *data = hci_get_drvdata(hdev); > + struct gpio_desc *reset_gpio = data->reset_gpio; > + > + /* > + * Toggle the hard reset line if the platform provides one. The reset > + * is going to yank the device off the USB and then replug. So doing > + * once is enough. The cleanup is handled correctly on the way out > + * (standard USB disconnect), and the new device is detected cleanly > + * and bound to the driver again like it should be. > + */ > + if (test_and_set_bit(BTUSB_HW_RESET_DONE, &data->flags)) { > + bt_dev_warn(hdev, "last reset failed? Not resetting again\n"); > + return; > + } > + > + bt_dev_dbg(hdev, "Initiating HW reset via gpio\n”); The bt_dev_ functions don’t need the \n at the end. > + gpiod_set_value(reset_gpio, 1); > + mdelay(100); > + gpiod_set_value(reset_gpio, 0); > +} > + > static inline void btusb_free_frags(struct btusb_data *data) > { > unsigned long flags; > @@ -2915,6 +2943,7 @@ static int btusb_probe(struct usb_interface *intf, > const struct usb_device_id *id) > { > struct usb_endpoint_descriptor *ep_desc; > + struct gpio_desc *reset_gpio; > struct btusb_data *data; > struct hci_dev *hdev; > unsigned ifnum_base; > @@ -3028,6 +3057,16 @@ static int btusb_probe(struct usb_interface *intf, > > SET_HCIDEV_DEV(hdev, &intf->dev); > > + reset_gpio = gpiod_get_optional(&data->udev->dev, "reset", > + GPIOD_OUT_LOW); > + if (IS_ERR(reset_gpio)) { > + err = PTR_ERR(reset_gpio); > + goto out_free_dev; > + } else if (reset_gpio) { > + data->reset_gpio = reset_gpio; > + hdev->hw_reset = btusb_hw_reset; > + } > + > hdev->open = btusb_open; > hdev->close = btusb_close; > hdev->flush = btusb_flush; > @@ -3083,6 +3122,7 @@ static int btusb_probe(struct usb_interface *intf, > set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks); > set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks); > set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks); > + set_bit(HCI_QUIRK_HW_RESET_ON_TIMEOUT, &hdev->quirks); > > if (id->driver_info & BTUSB_INTEL) { > hdev->setup = btusb_setup_intel; > @@ -3223,6 +3263,8 @@ static int btusb_probe(struct usb_interface *intf, > return 0; > > out_free_dev: > + if (data->reset_gpio) > + gpiod_put(data->reset_gpio); > hci_free_dev(hdev); > return err; > } > @@ -3266,6 +3308,9 @@ static void btusb_disconnect(struct usb_interface *intf) > if (data->oob_wake_irq) > device_init_wakeup(&data->udev->dev, false); > > + if (data->reset_gpio) > + gpiod_put(data->reset_gpio); > + > hci_free_dev(hdev); > } Regards Marcel